Efectividad de la vacuna antivaricela como profilaxis post exposición en niños chilenos / Effectiveness of varicella vaccine as post exposure prophylaxis in Chilean children

Introduction: Efficacy and effectiveness of varicella vaccine (VV) as post exposure prophylaxis (PEP) strategy have shown discordant results for disease risk reduction, and more consistent results in their ability to attenuate the disease. Aim: To assess the effectiveness of VV as PEP among household contacts. Material and Methods: We followed up 33 children after household exposure to a varicella case, of which 15 received VV as PEP and 18 did not received VV. The presence and severity of the disease were clinically determined. Results: Secondary attack rate was 53% among vaccinated and 89% among non-vaccinated children. Overall effectiveness of VV as PEP was 40% (CI95% 1%-64%). The effectiveness for preventing moderate or severe disease was 63% (CI95% 8%-85%) in the entire group and 77% (CI95% 14%-94%) among children vaccinated during the first 3 days post exposure. Vaccine tolerance was acceptable, with a low number of adverse reactions, all of them mild. Conclusion: The results suggest that VV as PEP is effective among household contacts, especially for reducing the severity of the disease.

Introducción: Los estudios de eficacia y efectividad de la vacuna antivaricela (V AV) como profilaxis post exposición (PPE) han mostrado resultados disímiles en cuanto a la reducción del riesgo de enfermar, y algo más consistentes en su capacidad de atenuar la enfermedad. Objetivo: Evaluar la efectividad de la VAV como PPE utilizada en contactos domiciliarios. Material y Métodos: Se realizó el seguimiento post exposición de 33 contactos domiciliarios de casos de varicela, de los cuales 15 recibieron VAV como PPE y 18 no la recibieron. Se determinó clínicamente el desarrollo de enfermedad y la intensidad de la misma. Resultados: La tasa de ataque secundario fue 53% en vacunados y 89% en no-vacunados, siendo la efectividad global de la VAV como PEP 40% (IC95% 1%-64%). La efectividad para prevenir enfermedad moderada o intensa fue 63% (IC95% 8-85%) en el grupo completo y 77% (IC95% 14-94%) en los niños vacunados durante los primeros tres días post exposición. La tolerancia a la vacuna fue aceptable, con un bajo número de reacciones adversas, todas leves. Conclusión: Los resultados sugieren que la VAV es efectiva como PPE en contactos domiciliarios, especialmente para reducir la intensidad de la enfermedad.

Varicela: consultas frecuentes acerca de su tratamiento y el manejo de los contactos / Varicella: frequent questions on treatment and recommendations for management of contacts

Dealing with varicella often causes doubts to general practitioners and pediatricians. In this article the author summaries guidelines based on solid evidence to treat varicella and prevent the disease in susceptible contacts in different clinical scenarios and presents his personal point of view in those controversial aspects commonly resolved by the authorized opinión of experts.

El manejo de la varicela despierta, con alta frecuencia, dudas en los médicos generales y pediatras. En este artículo, el autor resume aquellas recomendaciones basadas en sólida evidencia, para tratar la varicela y prevenir la enfermedad en los contactos susceptibles de un caso índice, en diferentes situaciones clínicas. Además emite su personal punto de vista en aquellos aspectos que despiertan controversia y comúnmente son resueltos en base a la opinión de reconocidos expertos.

Maternal chickenpox in peripartum period: a case report and review.

A 30-year-old pregnant woman had skin lesions at 38 weeks of gestation. She was diagnosed as primary varicella zoster infection. Her clinical symptoms were high fever and generalized vesicles eruption. No serious maternal complication was found. The patient delivered a male baby 4 days after she developed skin lesions. The neonatal blood IgM against varicella zoster was negative. The baby was given Varicella zoster immunoglobulin within 24 hours and isolated in a neonatal care unit. The baby developed skin lesions on day 11th post delivery. Intravenous acyclovir was administered for 7 days. Finally, the baby was found to be free of severe neonatal varicella infection.

Herpes zoster in a five month old infant subsequent to intrauterine exposure to varicella infection.

Herpes zoster is characterized by painful vesicular eruption in a dermatomal distribution of sensory nerves as a result of reactivation of latent herpes zoster virus in posterior root ganglia. The primary varicella infection is usually acquired in childhood and reactivation usually is seen in elderly. In rare instances herpes zoster can also occur in infancy as a result of reactivation of primary varicella infection acquired in utero or in early infancy. Here, we report a rare case of herpes zoster in a 5 month baby who acquired primary infection in utero from mother who had varicella infection at 6 months of gestation.

Surtos de varicela em creches na Capela do Socorro em 2005 / Varicella outbreak in the Capela do Socorro, 2005

A varicela é uma doença causada pelo vírus varicela-zoster. A varicela é extremamente transmissível sendo transmitida de pessoa à pessoa, com risco maior em ambientes fechados, como creches, salas de aula e enfermarias...

The varicella disease is caused by a varicella-zoster virus. The varicella is extremely transmissible, being transmitted from person to person, its greater risk is on closed ambient as foundling-hospitals, class rooms and sick-rooms. The vaccine is insure and immune to children, healthy adults and in free compromising patients it shows good tolerability with few collateral reactions having an efficacy of 80%. The goal of this work has being to analyze the varicella outbreak occurred in 2005 at Capela do Socorro region. The study done was transversal, through outbreak data ocurred in foundlings during the year of 2005 in theregion Capela do Socorro Health Vigillancy Supervising (SUVIS). In the present study, 36 establishments have been analysed, having at least one varicella outbreak and showing a total of 617 cases out of a group of 6845 members, with an attack tax of 9,01%. The data obtained has shown predominance on an age of 1-4 years (x2=195.50) in the winter months (61,11% of the outbreak) and a major outbreak numbers on near institutions to Veleiros, Republica and Mirna, respectively. The CEI José Molina has been the one that presented major attack tax (38,46%). Due to the great transmissibility of varicella and to the extreme rapidity that it can be disseminated in confined ambients as foundlings, is the reason of the importance of a study related to the foundlings as those of the Capela do Socorro...

Occupational and nosocomial transmission of varicella

We examined varicella transmission in a hospital specialized in cancer treatment. A cases series study was made of a case of intra-hospital transmission of varicella, based on a revision of the records of patients who had been admitted during the time the index case was in the same service. Records of interviews of employees were also reviewed. During the period that the index case was in the intensive care unit, 34 patients were admitted and 35 employees worked there. Two employees and a patient developed the illness, due to transmission directly or indirectly from the index case. Although this is a service in which most of the patients are adults who have cancer, attention needs to be directed towards diagnosis and to procedures to reduce the transmission of this illness, both to healthcare professionals, and to other patients. A standard schedule for varicella prevention already exists; however, this case reinforces the need for specific vaccination of at-risk professionals.

Medidas de controle em comunicantes de varicela em ambiente hospitalar / Control measures for transmitters of varicella in a hospital environment

Neste período do ano, na primavera, a varicela tem seu pico de incidência anual. Apesar de ser desejável que todas as crianças tivessem recebido a vacina contra a varicela, esta ainda não é a realidade no nosso meio. Assim, esta doença infecto-contagiosa de altíssima transmissibilidade ocorre ainda hoje no ambiente hospitalar e é motivo de sérios problemas...

Tuberculosis, chickenpox and scabies outbreaks in an orphanage for children with HIV/AIDS in Jamaica

OBJECTIVES: The aim of this study is to describe the investigation and management of outbreaks of acute tuberculosis, varicella zoster virus and scabies in a residential facility for children with HIV/AIDS. METHOD: A review of the results and management for diagnosed cases of acute TB (four between 2001 and 2002) as well as varicella zoster virus (15) and scabies (14) (concurrent in March--June 2003), in a residential facility housing 24 abandoned children with HIV/AIDS was conducted. Outbreak control methods and challenges are described The modified WHO criteria were used for TB diagnosis. The diagnoses of varicella and scabies were entirely clinical. RESULTS: Of the surviving 22 children, 12 (mean age 8 years 2 months) were female, and 10 (mean age 5 years 6 months) were male. Full immunization (primary series) was documented for 16 children, partial in one child, unknown status was documented in five children. One child had received varicella vaccine previously. Eleven (50) children had been receiving antiretroviral triple therapy since 2002 (all in Centers for Diseases Control immunological categories 2-3). Two of the four children with tuberculosis died between 2001 and 2002; these were not on antiretroviral therapy--the 2 survivors are still on antiretroviral therapy. All staff mantoux test results were negative. Fifteen (68) children developed chickenpox as well as three caregivers. The index case was a 13-year-old resident attending a nearby school with HIV negative children. This varicella outbreak went on to affect household members for the caregivers as well as other residential facilities nearby. Scabies affected 14 children (no caregivers); the index cases were most likely three new child residents who entered the institution in 2002 (from other homes) with histories of scabies infestation. Chickenpox and scabies dual infection occurred in seven (31) of residents. No cases of herpes zoster, disseminated varicella infection or death because of varicella occurred Diagnosed cases of chickenpox were treated with oral acyclovir Knowledge about these disease outbreaks and their control was generally lacking. CONCLUSIONS: Improvement in immunization coverage for children and staff as well as educating staff about infectious disease outbreaks, is necessary for effective control. Appropriate screening for infection/disease for all susceptible persons is essential along with timely reporting of outbreaks/reportable diseases. There is need for in

Three year seroepidemiological study of varicella-zoster virus in São Paulo, Brazil

A serosurvey of varicella has been carried out in children attending the public school network of São Paulo city, Brazil, from 1992 to 1994. This study was performed in order to establish the age related prevalence of antibodies against varicella-zoster virus (VZV) and its age specific transmission dynamics pattern in these children. Among 2500 schools in the city of São Paulo public network, 304 were randomly selected; 7 children of a given age (ranging from 1 to 15 years) were randomly selected in each school, and blood samples were obtained by fingerprick into filter paper. Blood eluates were analyzed for the presence of antibodies to VZV by ELISA. Proportion of seropositivity were calculated for each age group. Samples consisted of 1768 individuals in 1992, 1758 in 1993, and 1817 in 1994, resulting in 5343 eluates. A high proportion of seropositive children from 1 to 3 years of age was observed, ascending until 10 years of age and reaching a plateau around 90 percent afterwards. VZV transmission in this community was similar along the three years of the study. In children attending public schools in the city of São Paulo, contact with VZV occurs in early childhood. If immunization against VZV is considered it should be introduced as soon as possible.